Take a look at America's 10 richest families

The billionaire billboard

The top 25 wealthiest families in America are worth $722 billion, down 1.5 percent, or $11 billion, from a year ago.

Here’s who they are, according to Forbes:

1. Walton family

Net worth: $130bn

Wealth source: Walmart

2. Koch family

Net worth: $80bn

Wealth source: diversified

3. Mars family

Net worth: $78bn

Wealth source: candy

4. Cargill-MacMillan family

Net worth: $49bn

Wealth source: Cargill Inc

5. Cox family

Net worth: $41bn

Wealth source: media

6. SC Johnson family

Net worth: $30bn

Wealth source: cleaning products

7. Pritzker family

Net worth: $29bn

Wealth source: hotels and investments

8. Edward Johnson family

Net worth: $28.5bn

Wealth source: money management

9. Hearst family

Net worth: $25bn

Wealth source: Hearst Corp

10. Duncan family

Net worth: $21.5bn

Wealth source: pipelines